Report/Guide

Thomas, D J; Bunce, M (2022) Features of the neutron spectra produced using the tritium targets currently available for neutron production with the T(d,n)4He reaction at NPL - June 2022. NPL Report. IR 62

Thomas, D J (2021) Air attenuation corrections for neutron calibrations. NPL Report. IR 58

Thomas, D J; Roberts, N J (2018) Characterisation of a long counter for JRC Geel. NPL Report. IR 52

Thomas, D J; Roberts, N J (2017) Absolute neutron emission measurements for two neutron generators. NPL Report. IR 44

Kolkowski, P K; Thomas, D J (2013) The NPL contribution to CCRI key comparison K8 of thermal neutron fluence measurements. NPL Report. IR 29

McKay, C J; Burgess, P; Hawkes, N P; Kelly, M; Taylor, G C; Thomas, D J (2009) Photon does in NPL standard radionuclide neutron fields. NPL Report. IR 12

Roberts, N J; Duane, S; Judge, S M; de Lavison, P A G; Rayner, D; Thomas, D J; Zeqiri, B (2007) Proposed NMS programme for acoustics and ionising radiation metrology - October 2007 to September 2010: public comment. NPL Report. DQL-RN 020

Thomas, D J; Kolkowski, P; Roberts, N J; Mellow, B D*; Joyce, M J* (2006) Investigation of a possible replacement for cadmium as a thermal neutron absorbing material in neutron instruments. NPL Report. DQL-RN 017

Thomas, D J; Kolkowski, P (2005) Thermal fluence and dose equivalent standards at NPL. NPL Report. DQL-RN 008

Roberts, N J; Tagziria, H; Thomas, D J (2004) Determination of the effective centres of the NPL long counters. NPL Report. DQL-RN 004

Gressier, V*; Lacoste, V*; Lebreton, L*; Muller, H*; Pelcot, G*; Bakali, M*; Fernandez, F*; Tomas, M*; Roberts, N J; Thomas, D J; Reginatto, M*; Wiegel, B*; Wittstock, J* (2004) Characterization of the IRSN facility CANEL/T400 producing realistic neutron fields for calibration and test purposes. Technical Report. Institut de Radioprotection et de Surete Nucleaire.

Tanner, R J*; Thomas, D J; Bartlett, D T*; Hager, L G*; Horwood, N; Taylor, G C* (2002) Effect of the energy dependence of response of neutron personal dosemeters routinely used in the UK on the accuracy of dose estimation. Technical Report. NRPB.

Thomas, D J; Roberts, N J; Bennett, A; Kolkowski, P (2002) The NPL contribution to a CCRI international comparison of fast neutron fluence measurements performed at the PTB in March 2001. NPL Report. CIRM 51

Tagziria, H; Roberts, N; Bennett, A; Thomas, D J (2001) Calibration and Monte Carlo modelling of the NPL long counters at 22.8 keV. NPL Report. CIRM 48

Bartlett, D T*; Tanner, R J*; Tagziria, H; Thomas, D J (2001) Response characteristics of neutron survey instruments. Technical Report. NRPB, UK.

Thomas, D J (2001) NPL contribution to an international comparison of 24.5 keV neutron fluence measurements. NPL Report. CIRM 46

Kolkowski, P; Thomas, D J (1999) Measurement of the fast neutron component in the beam of the NPL Thermal Neutron Column using a Bonner sphere spectrometer. NPL Report. CIRM 28

Thomas, D J; Horwood, N; Taylor, G C (1999) Neutron dosemeter responses in workplace fields and the implications of using realistic neutron calibration fields. NPL Report. CIRM 27

Bardell, A G; Burke, M; Hunt, J B; Thomas, D J (1998) Anisotropy of emmision from radionuclide neutron sources. NPL Report. CIRM 24

Tagziria, H; Thomas, D J (1998) A high resolution neutron spectrometry system for the 50 to 1500 keV energy region. NPL Report. CIRM 21

Tagziria, H; Thomas, D J (1998) Re-calibration and Monte Carlo modelling of the NPL counters. NPL Report. CIRM 19

Taylor, G C; Thomas, D J (1998) Neutron scatter characteristics of the low-scatter facility of the Chadwick Building, NPL. NPL Report. CIRM 17

Thomas, D J; Taylor, G C (1998) Characteristics of multi-energy irradiation fields for determining the near-threshold response of fast-neutron personal dosemeters. NPL Report. CIRM 10

Drew, D W; Thomas, D J (1998) Measurements of the response functions of PADC track-etch and NTA film personal neutron dosemeters over the energy range from 100 keV to 5 MeV. NPL Report. CIRM 11

Thomas, D J; Bartlett, D T*; Burke, M; Horwood, N; Tanner, R J*; Taylor, G C (1997) Response characteristics of PADC track-etch and NTA film neutron personal dosemeters for backscatter from standard calibration phantoms. NPL Report. CIRM 7

Naismith, O F; Thomas, D J (1996) MCNP calculation of neutron scatter in the main bay of the Chadwick building, NPL. NPL Report. CIRA(EXT)004

Article

Chevallier, M A; Fantuzzi, E; Hajek, M; Meyer, S; Tanner, R; Thomas, D J; Vanhavere, F (2023) Analysis of EURADOS neutron intercomparison results according to new ISO standards criteria. Radiation Protection Dosimetry, 199 (15-16). pp. 1729-1734.

Mendez, R; Gomez-Ros, J M; Thomas, D J; Thompson, A K; Bedogni, R (2021) Revision of the Cf-252 and D2O-moderated Cf-252 reference neutron fields for use in radiation protection dosimetry. Radiation Physics and Chemistry, 184. 109433

Hawkes, N P; Kolkowski, P; Roberts, N J; Salvador-Castiñeira, P; Taylor, G C; Thomas, D J (2018) Additional characterisation of the Thermal Neutron Pile at the National Physical Laboratory, UK. Radiation Protection Dosimetry, 180 (1-4). pp. 25-28. ISSN 0144-8420

Bedogni, R; Pola, A; Costa, M; Monti, V; Thomas, D J (2018) A Bonner Sphere Spectrometer based on a large (Lil)-Li-6(Eu) scintillator: calibration in reference monoenergetic fields. Nuclear Instruments & Methods in Physics Research Section A - Accelerators Spectrometers Detectors and Associated Equipment, 897. pp. 18-21.

Salvador-Castiñeira, P; Hambsch, F-J; Göök, A; Vidali, M; Hawkes, N P; Roberts, N J; Taylor, G C; Thomas, D J (2017) Absolute and relative cross section measurements of 237Np(n,f) and 238U(n,f) at the National Physical Laboratory. EPJ Web of Conferences, 146. 04050 ISSN 2100-014X

Roberts, N J; Thomas, D J; Visser, T P P (2017) Improved Bonner sphere neutron spectrometry measurements for the nuclear industry. Radiation Physics and Chemistry, 140. pp. 319-321.

Matei, C; Belloni, F*; Heyse, J*; Plompen, A J M*; Thomas, D J (2017) Absolute cross section measurements of neutron-induced fission of Pu-242 from 1 to 2.5 MeV. Phys. Rev. C, 95 (2). 024606

Hawkes, N P; Thomas, D J; Taylor, G C (2016) Corrections associated with on-phantom calibrations of neutron personal dosimeters. Radiat. Prot. Dosim., 170 (1-4). pp. 35-38.

Chevallier, M A*; Fantuzzi, E*; Cruz-Suarez, R*; Luszik-Bhadra, M*; Mayer, S*; Thomas, D J; Tanner, R*; Vanhavere, F* (2016) EURADOS IC2012N: further information derived from an EURADOS international comparison of neutron personal dosmeters. Radiat. Prot. Dosim., 170 (1-4). pp. 78-81.

Nolte, R*; Bottger, R*; Chen, J*; Harano, H*; Thomas, D J (2015) International key comparison of thermal neutron fluence measurements - CCRI(III)-K8. Metrologia, 52 (1A). 06011.

Roberts, N J; Jones, L N; Liu, Z Z; Tagziria, H; Thomas, D J (2014) Bonner sphere measurements of 241Am-B and 241Am-F neutron energy spectra unfolded using high resolution a priori data. Radiat. Prot. Dosim., 161 (1-4). pp. 225-228.

Atanackovic, J*; Thomas, D J; Roberts, N J; Witharana, S*; Dubeau, J*; Yonkeu, A* (2014) Correction and verification of AECL Bonner Sphere response function matrix based on mono-energetic neutron calibration performed at NPL. Radiat. Prot. Dosim., 161 (1-4). pp. 216-220.

Fantuzzi, E*; Chevallier, M A*; Cruz-Suarez, R*; Luszik-Bhadra, M*; Mayer, S*; Thomas, D J; Tanner, R*; Vanhavere, F* (2014) EURADOS IC2012N: EURADOS 2012 intercomparison for whole-body neutron dosimetry. Radiat. Prot. Dosim., 161 (1-4). pp. 73-77.

Gressier, V*; Bonaldi, A C*; Dewey, M S*; Gilliam, D M*; Harano, H*; Masuda, A*; Matsumoto, T*; Moiseev, T*; Nico, J S*; Nolte, R*; Oberstedt, S*; Roberts, N J; Rottger, S*; Thomas, D J (2014) International key comparison of neutron fluence measurements in monoenergetic neutron fields - CCRI(III)-K11. Metrologia, 51 (1A). 06009.

Bedogni, R*; Domingo, C*; Roberts, N J; Thomas, D J; Chiti, M*; Esposito, A*; Garcia, M J*; Gentile, A*; Liu, Z Z*; de-San-Pedro, M* (2014) Investigation of the neutron spectrum of americium-beryllium sources by Bonner sphere spectrometry. Nucl. Instrum. Methods Phys. Res. A, Accel. Spectrom. Detec. Assoc. Equip., 763. pp. 547-552.

Thomas, D J (2014) The system of radiation protection for neutrons: does it fit the purpose? Radiat. Prot. Dosim., 161 (1-4). pp. 3-10.

Nolte, R*; Thomas, D J (2011) Monoenergetic fast neutron reference fields (part II): field characterisation. Metrologia, 48 (6). S274-S291

Nolte, R*; Thomas, D J (2011) Monoenergetic fast neutron reference fields: I. Neutron production. Metrologia, 48 (6). S263-S273

Thomas, D J; Nolte, R*; Gressier, V* (2011) Neutron metrology. Metrologia, 48 (6). Foreword

Thomas, D J; Nolte, R*; Gressier, V* (2011) What is neutron metrology and why is it needed? Metrologia, 48 (6). S225-S238

Roberts, N J; Thomas, D J; Lacoste, V*; Böttger, R*; Loeb, S* (2010) Comparison of long counter measurements of monoenergetic and radionuclide source-based neutron fluence. Radiat. Meas., 45 (10). pp. 1151-1153.

Lamirand, V*; Gressier, V*; Martin, A*; Thomas, D J (2010) Comparison of nuclear reactions for the production of monoenergetic neutron fields with energies below 100 keV. Radiat. Meas., 45. pp. 1112-1115.

Thomas, D J; Lewis, V E; Klein, H*; Allisy-Roberts, P J* (2010) International key comparison of 24 keV neutron fluence measurements (1993-2009): CCRI(III)-K1. Metrologia, 47. 06014.

Thomas, D J (2010) Neutron spectrometry. Radiat. Meas., 45 (10). pp. 1178-1185.

Lamirand, V*; Thomas, D J; Gressier, V*; Sorieul, S*; Liatard, E* (2010) Study of scandium targets for production of monoenergetic neutron fields with energies below 100 keV. Radiat. Meas., 45 (10). pp. 1116-1119.

Lamirand, V*; Thomas, D J; Gressier, V*; Sorieul, S*; Liatard, E* (2010) Study of scandium targets for production of monoenergetic neutron fields with energies below 100 keV. Radiat. Meas., 45 (10). pp. 1116-1119.

Thomas, D J; Hawkes, N P; Jones, L N; Kolkowski, P; Roberts, N J (2007) Characterization and utilization of a bonner sphere set based on gold activation foils. Radiat. Prot. Dosim., 126 (1-4). pp. 229-233.

Lebreton, L*; Zimbal, A*; Thomas, D J (2007) Experimental comparison of 241Am-Be neutron fluence energy distributions. Radiat. Prot. Dosim., 126 (1-4). pp. 3-7.

Hawkes, N P; Freedman, R; Tagziria, H; Thomas, D J (2007) Measurement and calculation of the emission anisotropy of an X1 252Cf neutron source. Radiat. Prot. Dosim., 126 (1-4). pp. 78-82.

Hawkes, N P; Bennett, A; Cheema, S S; Horwood, N A; Jones, L N; Kolkowski, P; Roberts, N J; Taylor, G C; Thomas, D J (2007) Progress in providing neutron standards at the UK National Physical Laboratory. Nucl. Instrum. Methods Phys. Res. A, Accel. Spectrom. Detec. Assoc. Equip., 580. pp. 183-185.

Taylor, G C; Thomas, D J; Bennett, A (2007) Results of field trials using the NPL simulated reactor neutron fields facility. Radiat. Prot. Dosim., 126 (1-4). pp. 89-92.

Aspinall, M D*; D'Mellow, B*; Mackin, R O*; Joyce, M J*; Hawkes, N P; Thomas, D J; Jarrah, Z*; Peyton, A J*; Nolan, P J*; Boston, A J* (2007) Verification of the digital discrimination of neutrons and gamma rays using pulse gradient analysis by digital measurement of time of flight. Nucl. Instrum. Methods Phys. Res. A, 583. pp. 432-438.

Tanner, R J*; Bartlett, D T*; Hager, L G*; Jones, L N; Molinos, C*; Roberts, N J; Taylor, G C; Thomas, D J (2005) Modelling of neutron survey instrument performance and experimental validation of those calculated response data. Radiat. Prot. Dosim., 116 (1-4). pp. 406-410.

Roberts, N J; Bartlett, D T*; Hager, L G*; Jones, L N; Molinos, C*; Tanner, R J*; Taylor, G C; Thomas, D J (2004) Angle dependence of response characteristics of neutron survey instruments. Radiat. Prot. Dosim., 110 (1-4). pp. 187-193.

Gressier, V*; Lacoste, V*; Lebreton, L*; Muller, H*; Pelcot, G*; Bakali, M*; Fernández, F*; Tómas, M*; Roberts, N J; Thomas, D J; Reginatto, M*; Wiegel, B*; Wittstock, J* (2004) Characterization of the IRSN CANEL/T400 facility producing realistic neutron fields for calibration and test purposes. Radiat. Prot. Dosim., 110 (1-4). pp. 523-527.

Gressier, V*; Lacoste, V*; Lebreton, L*; Muller, H*; Pelcot, G*; Bakali, M*; Fernández, F*; Tómas, M*; Roberts, N J; Thomas, D J; Reginatto, M*; Wiegel, B*; Wittstock, J* (2004) Characterization of the IRSN CANEL/T400 facility producing realistic neutron fields for calibration and test purposes. Radiat. Prot. Dosim., 110. pp. 523-527.

Gressier, V*; Lacoste, V*; Lebreton, L*; Muller, H*; Pelcot, G*; Bakali, M*; Fernández, F*; Tómas, M*; Roberts, N J; Thomas, D J; Reginatto, M*; Wiegel, B*; Wittstock, J* (2004) Characterization of the IRSN CANEL/T400 facility producing realistic neutron fields for calibration and test purposes. Radiat. Prot. Dosim., 110. pp. 523-527.

Thomas, D J (2004) Neutron spectrometry for radiation protection. Radiat. Prot. Dosim., 110 (1-4). pp. 141-149.

Tanner, R J*; Bartlett, D T*; Hager, L G*; Jones, L N; Molinos, C*; Roberts, N J; Taylor, G C; Thomas, D J (2004) Practical implications of neutron survey instrument performance. Radiat. Prot. Dosim., 110 (1-4). pp. 763-767.

Taylor, G C; Bentley, R D*; Horwood, N A; Hunter, R*; Iles, R H*; Jones, J B L*; Powell, D*; Thomas, D J (2004) TEPC measurements in commercial aircraft. Radiat. Prot. Dosim., 110 (1-4). pp. 381-386.

Taylor, G C; Thomas, D J; Bennett, A (2004) A realistic field facility to simulate reactor spectra. Radiat. Prot. Dosim., 110 (1-4). pp. 111-115.

Bartlett, DT*; Chartier, J-L*; Matzke, M*; Rimpler, A*; Thomas, D J (2003) Concepts and quantities in spectrometry and radiation protection. Radiat. Prot. Dosim., 107 (1-3). pp. 21-32.

Thomas, D J; Klein, H* (2003) Introduction (to Handbook on neutron and photon spectrometry techniques for radiation protection - special issue). Radiat. Prot. Dosim., 107 (1-3). pp. 13-21.

Tagziria, T; Roberts, N J; Thomas, D J (2003) Measurement of the 241Am-Li radionuclide neutron source spectrum. Nucl. Instrum. Methods Phys. Res. A, Accel. Spectrom. Detec. Assoc. Equip., 510. pp. 346-356.

Alevra, A V*; Thomas, D J (2003) Neutron spectrometry in mixed fields - multi-sphere spectrometers. Radiat. Prot. Dosim., 107 (1-3). pp. 37-72.

Klein, H*; Thomas, D J (2003) Quality assurance. Radiat. Prot. Dosim., 107 (1-3). pp. 175-188.

Thomas, D J; Alevra, A V* (2002) Bonner sphere spectrometers - a critical review. Nucl. Instrum. Methods Phys. Res. A, Accel. Spectrom. Detec. Assoc. Equip., 476 (1-2). pp. 12-20.

Thomas, D J; Bardell, A G; Macaulty, E M* (2002) Characterisation of a gold foil based bonner sphere and measurements of neutron spectra at a medical accelerator. Nucl. Instrum. Methods Phys. Res. A, Accel. Spectrom. Detec. Assoc. Equip., 476 (1-2). pp. 31-35.

Taylor, G C; Bentley, R D*; Conroy, T J*; Hunter, R*; Jones, J B L*; Pond, A*; Thomas, D J (2002) The evaluation and use of a portable TEPC system for measuring in-flight exposure to cosmic radiation. Radiat. Prot. Dosim., 99 (1-4). pp. 435-438.

Tanner, J G*; Thomas, D J; Bartlett, D T*; Hager, L G*; Horwood, N A (2002) The influence of the energy distribution of workplace fields on neutron personal dosemeter reading. Nucl. Instrum. Methods Phys. Res. A, Accel. Spectrom. Detec. Assoc. Equip., 476 (1-2). pp. 405-410.

Tagziria, H; Thomas, D J (2000) Calibration and Monte Carlo modelling of neutron long counters. Nucl. Instrum. Methods Phys. Res. A, Accel. Spectrom. Detec. Assoc. Equip., 452 (3). pp. 470-83.

Wu, M W*; Guung, T C*; Pei, C C*; Yang, T N*; Hwang, W S*; Thomas, D J (1999) Absolute neutron fluence measurements between 0.5 and 3 MeV and their intercomparisons. Nucl. Instrum. Methods Phys. Res. A, Accel. Spectrom. Detec. Assoc. Equip., 422 (1-3). pp. 79-83.

Bartlett, D J*; Tanner, R J*; Thomas, D J (1999) Active neutron personal dosemeters - a review of current status. Radiat. Prot. Dosim., 86 (2). pp. 107-122.

Tanner, R J*; Thomas, D J; Bartlett, D T; Horwood, N (1999) Systematic errors in the readings of track etch neutron dosemeters caused by the energy dependence of response. Radiat. Meas., 31 (1-6). pp. 483-6.

McDonald, J C*; Alberts, W G*; Bartlett, D T*; Chartier, J L*; Eisenhauer, C M*; Schraube, H O E*; Schwartz, R B*; Thomas, D J (1997) Current status of an ISO working document on reference radiations: Characteristics and methods of production of simulated practical neutron fields. Radiat. Prot. Dosim., 70. pp. 323-325.

Naismith, O F; Siebert, B R L*; Thomas, D J (1997) Response of neutron dosemeters in radiation protection environments and investigation of techniques to improve estimates of dose equivalent. Radiat. Prot. Dosim., 70. pp. 255-260.

Thomas, D J; Chartier, J L*; Klein, H*; Naismith, O F; Posny, F*; Taylor, G C (1997) Results of a large scale neutron spectrometry and dosimetry comparison exercise at the Cadarache Moderator Assembly. Radiat. Prot. Dosim., 70. pp. 313-322.

Thomas, D J; Naismith, O (1995) Developments in neutron spectrometry for radiation protection. Proc. SPIE - Int. Soc. Opt. Eng., 2339. 251 - 255

Marsh, J W*; Thomas, D J; Burke, M (1995) High resolution measurements of neutron energy spectra from AmBe and AmB neutron sources. Nucl. Instrum. Methods Phys. Res., A366 (2-3). pp. 340-348.

Tanner, J G*; Witts, D*; Tanner, R J*; Bartlett, D T*; Burgess, P H*; Edwards, A A*; More, B R*; Taylor, G C; Thomas, D J (1995) An assessment of the feasibility of using Monte Carlo calculations to model a combined neutron/gamma electron personal dosemeter. Radiat. Prot. Dosim., 61 (1-3). pp. 183-186.

Thomas, D J; Alevra, A V*; Hunt, J B; Schraube, H O E* (1994) Experimental determination of the response of four Bonner sphere sets to thermal neutrons. Radiat. Prot. Dosim., 54 (1). 25 - 31

Marshall, M*; Thomas, D J; Perks, C A*; Naismith, O F (1994) Radiation quantities: significance of the angular and energy distribution of the radiation field. Radiat. Prot. Dosim., 54 (3-4). 239 - 248

Thomas, D J; Klein, H* (1993) EURADOS Working Group 7; radiation spectrometry in working environments. Radioprotection, 28. pp. 95-100.

Naismith, O F; Thomas, D J (1993) A performance test of UK personal dosimetry services for fast neutrons. Radiat. Prot. Dosim., 48 (4). pp. 333-340.

Conference or Workshop Item

Bentely, R D*; Iles, R H A*; Jones, J B L*; Hunter, R*; Taylor, G C; Thomas, D J (2001) Monitoring cosmic radiation on aircraft. In: Proceedings of the Second Solar Cycle and Space Weather Euroconference, 24-29 September 2001.

Iles, R H A*; Jones, J B L*; Bentley, R D*; Hunter, R*; Taylor, G C; Thomas, D J; Harra, L K*; Coates, A J* (2001) The effect of solar particle events at aircraft altitudes. In: Proceedings of ESA Space Weather Workshop, December 2001.

Jones, J B L*; Bentley, R D*; Hunter, R*; Taylor, G C; Thomas, D J (2001) The practical issues of utilising a European space weather programme for airline operations. In: Proceedings of ESA Space Weather Workshop, December 2001.

Thomas, D J; Taylor, G C (1997) Response function measurements for the REM 500: a microdosimetric counter based area survey instrument. In: Proc. International Conference on Radiation Dosimetry and Safety, 31 March-2 April 1997, Taipai, Taiwan, Republic of China.

Bardell, A G; Thomas, D J (1995) Calibration and type testing of neutron radiation protection instrumentation. In: Proc. International Conference on Radiation Dose Management in the Nuclear Industry, 9-11 November 1995, Windermere, Cumbria.

Bardell, A G; Thomas, D J (1995) Neutron spectrometry for protection dosimetry at very low levels. In: Proc. International Conference on Radiation Dose Management in the Nuclear Industry, 9 - 11 November 1995, Windermere, Cumbria.

Tan, M*; Weaver, D R*; Scott, M C*; Thomas, D J (1994) A new dose-equivalent counter for neutron area monitoring. In: Proc. Int. Conf. Neutrons and their applications, 12 - 18 June 1994, Crete, Greece.